Power supply systems are pervasive in many electronic applications from computers to automobiles. Generally, voltages within a power supply system are generated by performing a DC-DC, DC-AC, and/or AC-DC conversion by operating a switch loaded with an inductor or transformer. One class of such systems includes switched mode power supplies (SMPS).
An SMPS usually includes at least one switch and an inductor or transformer. Some specific topologies include buck converters, boost converters, and flyback converters, among others. A control circuit is commonly used to open and close the switch to charge and discharge the inductor. In some applications, the current supplied to the load and/or the voltage supplied to the load is controlled via a feedback loop.
Generally, the efficiency of a SMPS improves as the speed of the switch increases because the switching losses decrease. Accordingly, SMPS have been utilizing more advanced power semiconductor components such as Super-Junction Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) and Insulated Gate Bipolar Transistors (IGBTs) to increase the switching speed in SMPS. These advanced power semiconductor components have very low switching losses due to low internal parasitic capacitances and high switching speed. However, one of the side effects of high switching speeds is increased electromagnetic emissions, which presents challenges with respect to the designing a SMPS that is both power efficient and compliant with relevant electromagnetic interference (EMI) standards and requirements.